Multiple axis work-piece tranfser apparatus

ABSTRACT

A work-piece transfer apparatus, comprising at least one work-piece engagement structure; at least one first robot arm pivotally connected to the work-piece engagement structure; a first motor coupled to the first robot arm and being adapted for translating the first robot arm fore and aft in a generally horizontal direction; a second motor; at least one second robot arm being in operating driving relationship with the second motor and operatively coupled with the work-piece engagement structure for raising and lowering the work-piece engagement structure; and a support structure for supporting the apparatus or portions thereof; wherein the first motor and second motor are operated synchronously to raise, lower, and/or translate the work-piece engagement structure in a fore and aft direction by way of one or both of the first robot arm and second robot arm.

CLAIM OF BENEFIT OF FILING DATE

The present application claims the benefit of the filing date of U.S.Application Nos. 61/909,759, filed Nov. 27, 2013, and 62/041,348, filedAug. 25, 2014, both of which are incorporated by reference in theirentireties.

FIELD

In general, the present teachings relate to an improved work-piecetransfer apparatus, and particularly a work-piece transfer apparatusthat has multiple mechanical links driven by multiple servo motors thatcontrol work-piece engagement structures.

BACKGROUND

In various work-piece operation systems there is a need for transferringwork-pieces from one station to another to allow for differentoperations to be performed upon the work-piece. One approach totransferring work-pieces is to employ a walking beam apparatus.Transferring work-pieces may employ linear motion actuation methods.There is an ongoing need for an improved apparatus that is efficient,compact and requires relatively little maintenance. There is also anongoing need for an improved apparatus that can be efficientlycontrolled and operated, and can be used to advance multiple work piecesalong multiple stations in a work piece operation system.

SUMMARY

The present teachings meet one or more of the above needs by providingan improved work-piece transfer apparatus. The work-piece transferapparatus makes advantageous use of one or more robot arms for driving awork-piece support structure upward and downward, and generally in ahorizontal direction. The one or more robot arms can be employed toeffectuate a travel path that combines upward, downward, and/orhorizontal direction components. The one or more robot arms may be usedto create a walking beam apparatus.

The present teachings contemplate a work-piece transfer apparatus,comprising at least one generally elongated work-piece engagementstructure; at least one first robot arm having a first end portion and asecond end portion, the first end portion being pivotally connected tothe at least one generally elongated work-piece engagement structure; afirst motor coupled to the at least one first robot arm at the secondend portion and being adapted for translating the at least one robot armfore and aft in a generally horizontal direction; a second motor; atleast one second robot arm having a first end portion and a second endportion, the first end portion of the at least one second robot armbeing in operating driving relationship with the second motor, and thesecond end portion operatively coupled with the at least one generallyelongated work-piece engagement structure for raising and lowering theat least one generally elongated work-piece engagement structure; and anoptional support structure (e.g., a sub-plate or bolster plate) forsupporting the first and second motor, the at least one first robot arm,the at least one second robot arm, and the at least one generallyelongated work-piece engagement structure.

The present teachings contemplate a work-piece transfer apparatuscomprising: at least one generally elongated work-piece engagementstructure; a linear actuation motor coupled with the at least onegenerally elongated work-piece engagement structure, at least one firstrobot arm having a first end portion and a second end portion, the firstend portion being connected to the at least one generally elongatedwork-piece engagement structure; a first motor coupled to the at leastone first robot arm and at least one generally elongated work-pieceengagement structure; at least one second robot arm coupled with thesecond end portion of the at least one first robot arm; a second motorcoupled to the at least one first robot arm and the at least one secondrobot arm; a base for supporting the at least one first robot arm, theat least one second robot arm, and the at least one generally elongatedwork-piece engagement structure and mounting the apparatus to astructure; and a third motor coupled to the base and the at least onesecond robot arm; wherein the linear actuation motor is operated toprovide linear movement in a longitudinal or transverse direction inrelation to the structure; wherein the first motor is operated tomaintain a desired orientation of the at least one generally elongatedwork-piece engagement structure; and wherein the second and third motorsare operated synchronously to raise and lower the at least one generallyelongated work-piece engagement structure, and translate the at leastone generally elongated work-piece engagement structure in a fore andaft direction by way of one or both of the at least one first and secondrobot arms.

The present teachings relate generally to a work-piece transferapparatus comprising at least one generally elongated work piecestructure by robot arm arrangement. The robot arm arrangement mayinclude two or more robot arms, each arm adapted to be driven by atleast one motor (e.g., a servo motor). For example, a pair of robot arms(which may be located on the same side of the apparatus as each other)may be driven by a motor (e.g., a servo motor). The motors may beoperated synchronously to raise and lower the at least one generallyelongated work-piece engagement structure, and translate the at leastone generally elongated work-piece engagement structure in a fore andaft direction by way of one or both of the at least one first and secondrobot arms.

One or more arms may be driven, by way of a gear reduction mechanism(e.g., a cycloid gear reduction mechanism). The gear reduction mechanismmay be integrally formed as part of a robot arm. For example, the robotarm may be configured to integrally have formed a structure to receive aplurality of collector pins that facilitate motion by a cycloid gear.

In general, the present teachings may include a work-piece transferapparatus, comprising at least one work-piece engagement structure; atleast one first robot arm pivotally connected to the work-pieceengagement structure; a first motor coupled to the first robot arm andbeing adapted for translating the first robot arm fore and aft in agenerally horizontal direction; a second motor; at least one secondrobot arm being in operating driving relationship with the second motorand operatively coupled with the work-piece engagement structure forraising and lowering the work-piece engagement structure; and a supportstructure for supporting the first and second motor, the first robotarm, the second robot arm, and the work-piece engagement structure;wherein the first and second motors are operated synchronously to raise,lower, and/or translate the work-piece engagement structure in a foreand aft direction by way of one or both of the first and second robotarms. Raising, lowering, or translation may be assisted or causedthrough one or more gear reduction mechanisms. The one or more gearreduction mechanisms may be at least partially housed within one or moreof the robot arms.

As part of the general teachings herein, applicable to the variousembodiments contemplated, it may be possible for one motor to be mountedto and carried on a structure translatable by another motor (e.g., amotor may be mounted to a robot arm that is translated by anothermotor). Thus, raising and lowering may be performed by one motor andpitch may be performed by another motor. Another motor may be used toprovide linear motion along a longitudinal or transverse axis of theapparatus or of a structure the apparatus is associated with.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an apparatus in accordance with thepresent teachings.

FIG. 2 is a side view of the apparatus of FIG. 1.

FIG. 3 is a top view of an end portion of the apparatus of FIG. 1.

FIG. 4A is a side view of an arm useful in the apparatus of FIG. 1.

FIG. 4B is a sectional view of a corner portion of the apparatus of FIG.1.

FIG. 5 is a sectional perspective view of a gear reduction mechanism ofthe present teachings.

FIG. 6 is another sectional perspective view of a gear reductionmechanism of the present teachings that omits a mounting foot.

FIG. 7 is a plan view of a section of the mechanism of FIG. 5.

FIG. 8 is a transparent perspective view of the mechanism of FIG. 5.

FIG. 9 if a sectional view of a portion of the mechanism of FIG. 5.

FIGS. 10A and 10B are exploded views of a gear reduction mechanism ofthe present teachings.

FIG. 11A is a perspective view of a drive shaft attachment portion.

FIGS. 11B and 11C are cross sections of a portion of the drive shaftattachment portion taken along line B,C.

FIGS. 12A, 12B, 12C, 12D, and 12E are perspective views of an apparatusof the present teachings shown in various stages of advancing awork-piece along the length of the apparatus.

FIG. 13 is a perspective view of an apparatus of the present teachings.

FIG. 14 is a perspective view of an apparatus of the present teachingsmounted to a bolster plate of a press.

FIG. 15 is a perspective view of an apparatus of the present teachingsmounted to upright support members of a press.

DETAILED DESCRIPTION

As required, detailed embodiments of the present teachings are disclosedherein; however, it is to be understood that the disclosed embodimentsare merely exemplary of the teachings that may be embodied in variousand alternative forms. The figures are not necessarily to scale; somefeatures may be exaggerated or minimized to show details of particularcomponents. Therefore, specific structural and functional detailsdisclosed herein are not to be interpreted as limiting, but merely as arepresentative basis for teaching one skilled in the art to variouslyemploy the present teachings.

While exemplary embodiments are described above, it is not intended thatthese embodiments describe all possible forms of the teachings. Rather,the words used in the specification are words of description rather thanlimitation, and it is understood that various changes may be madewithout departing from the spirit and scope of the teachings.Additionally, the features of various implementing embodiments may becombined to form further embodiments of the teachings.

By way of illustration, the present teachings may include a work-piecetransfer apparatus, comprising at least one work-piece engagementstructure; at least one first robot arm pivotally connected to thework-piece engagement structure; a first motor coupled to the firstrobot arm and being adapted for translating the first robot arm fore andaft in a generally horizontal direction (or for raising and lowering thework-piece engagement structure); a second motor; at least one secondrobot arm being in operating driving relationship with the second motorand operatively coupled with the work-piece engagement structure forraising and lowering and/or translating (e.g., fore and aft in agenerally horizontal direction) the work-piece engagement structure; anda support structure for supporting the first and second motor, the firstrobot arm, the second robot arm, and the work-piece engagementstructure; wherein the first and second motors are operatedsynchronously to raise, lower, and/or translate the work-pieceengagement structure in a fore and aft direction by way of one or bothof the first and second robot arms. The teachings herein also include athird motor for effectuating additional movement of the apparatus (e.g.,creating another axis of movement).

The teachings herein envision a work-piece transfer apparatus (such as awalking beam apparatus) that includes at least one work-piece engagementstructure (e.g., a bar, an element for supporting and/or attachment oftools for holding a work-piece, or other surface) adapted for engaging awork-piece and transferring the work-piece within a work-piece operationsystem adapted for performing one or more operations upon the work-piece(e.g., shaping the work-piece (e.g., by a press), attaching two or morecomponents of the work-piece (e.g., by one or more of welding, byfastening, by adhering, by crimping, or otherwise)), at the work-pieceoperation system's progressive operation stations. A lifting robot armdevice operatively engages the work-piece engagement bar, the robot armdevice being adapted for translation upwardly and downwardly, andhorizontally in the work-piece transfer direction and horizontally inthe direction opposite to the work-piece transfer direction relative tothe work-piece operation system. As with all robot arm translationteachings herein, it will be appreciated that the above thus alsocontemplates a combined series of minute translations, the effect ofwhich is to give the appearance of one or more arcuate motions.Optionally, a second rearward work-piece engagement bar may beoperatively engaged by arms attached to the robot arms by a shaftconnected to the first robot arm that rotates at the same center as therobot arms. The lifting robot arm may be motor driven, and may besynchronously controlled in a manner so that when the lifting robot armdevices translates upwardly, downwardly, and/or horizontally, anotheroptional lifting robot arm device may also translate generally upwardly,downwardly, and/or horizontally in a substantially similar manner. Oneor more of the lifting robot arm devices may include a mounting portionadapted to be mounted in a fixed position relative to the work-pieceoperation system (e.g., to a sub-plate or bolster plate). The robot armsmay include a first arm pivotally connected to the mounting portion at afirst joint. At least one second arm may be pivotally connected to thefirst arm at at least one second joint. The at least one second arm maybe connected to a work-piece engagement bar for the purpose of providingthe horizontal movement to the work-piece engagement bar(s). The secondarm may be motor driven, and the second horizontal movement robot armmay be linked to the motor driven horizontal movement robot arm deviceby the work-piece engagement bar(s) such that when one of the horizontalmovement robot arm devices translates horizontally, the other horizontalmovement robot arm device also translates generally horizontally in asubstantially similar manner. The arms can be any size or shapedepending on the application. It is also contemplated that otherconfigurations of the assembly may include a first arm that translatesgenerally horizontally and a second arm that translates generallyupwardly and/or downwardly. It is thus possible that a subassembly mayinclude a first motor that is maintained in a stationary positionrelative to a support structure of the assembly. At least one secondmotor may be married on a robot arm and thus may have its positionmoved, such as relative to a support structure.

The walking beam work-piece transfer apparatus may include one or moremotors (e.g., a servo motor), such as a motor adapted for closed loopcontrol based on sensing the location of the output shaft. The motor maybe adapted to be controllably operated and may have inputs for power andfor communicating with a suitable controller (e.g., a programmable logiccontroller). A suitable controller may control the operation of themotor based upon signals from the motor that correspond with apositional location of the motor output (e.g., a drive shaft). The motormay have a drive shaft. The drive shaft may be generally cylindrical inits outer shape. One or more motors may also include a motor adapterplate that allows the motor to be attached to a base within theassembly, allows the motor to engage with a gear reduction mechanism, orboth. The assembly may include a motor (e.g., a Schneider Electricmotor, Model No. BMH100/P12A2A or one having similar structural and/orfunctional characteristics, whether having similar power output or not),an elongated drive shaft attachment portion (e.g., a coupler), and oneor more gear reduction mechanisms (e.g., a gear box).

The elongated drive shaft attachment portion may include a first motorconnection portion adapted to be connected with the output shaft of themotor and a second gear box interface portion adapted to interface witha gear reduction mechanism. It is also contemplated that the motoroutput shaft (e.g., drive shaft) may be integrally formed with theelongated drive shaft attachment portion. The first motor connectionportion may be adapted to be press-fitted or otherwise assembled ontothe motor output shaft (e.g., drive shaft). For example, the elongateddrive shaft attachment portion may have a longitudinal axis (e.g.,generally aligned with the longitudinal axis of the motor drive shaft)that is oblong on an inside wall in its transverse cross-section. Theelongated drive shaft attachment portion may be adapted to change thetransverse cross-sectional shape in response to an applied pressure sothat the shape generally corresponds with the shape of the motor outputshaft (e.g., drive shaft). When the pressure is applied, the elongateddrive shaft attachment portion may be placed over the motor output shaft(e.g., drive shaft). When the pressure is released, the elasticity ofthe material (e.g., a suitable spring steel, such as AISI 1095 gradesteel) may cause the inner wall to return toward its original shape,thereby engaging the drive motor output (e.g., drive shaft) in apress-fit manner. The elongated drive shaft attachment portion may havea wall thickness of about 10 mm or less (e.g., in a range of about 1 mmto about 7 mm or about 2 mm to about 5 mm).

The elongated drive shaft attachment portion may join the first motorconnection portion and the gear box interface portion. The gear boxinterface portion may have an engagement portion (e.g., at an endopposite the motor connection portion) adapted to fittingly interfacewith the gear reduction mechanism. The gear reduction mechanism may havea complementary shape structure for connection with the elongated driveshaft attachment portion. For example, the engagement portion may have amale or female connector portion that engages respectively an opposingmale or female connector portion (e.g., of the gear reductionmechanism). One particular possibility is to have the engagement portionhave at least one surface oriented relative (e.g., generally parallel orat some angle less than about 75°) to the longitudinal axis that has aflat component. For example, it may be generally rectangular.

The gear reduction mechanism may have one or more stages of gearreduction. One or both of the motors may drive a cycloid gear reductionmechanism associated with one or more of the robot arms. For instance, acycloid gear reduction mechanism may be integrally mounted to and formedas part of the first arm, the second arm or both. One or both of themotors may drive a planetary gear reduction mechanism associated withone or more of the robot arms. A single motor may drive an individualrobot arm. A single motor may drive multiple arms. One or more arms maybe employed that are not associated and/or do not contain a gearreduction mechanism and/or an attached motor. For instance, such armsmay be located in the apparatus on a side of the apparatus opposite thedriving arms, and/or on the same side as the driving arms but downstreamfrom them. A width between opposing work-piece engagement bars may beadjustable along a common shaft.

As indicated, a cycloid gear reduction mechanism, planetary gearreduction mechanism, or other gear reduction mechanism may be employed(e.g., between a motor and a robot arm). A gear reduction mechanism maybe at least partially integrated into a robot arm and may be inoperative driving relationship with one or more of the motors. Any gearreduction mechanism employed may have a reduction ratio of at leastabout 2:1, 3:1, 4:1, 6:1, 10:1, 30:1, 50:1, 90:1, or even 150:1. Acycloid gear assembly, planetary gear assembly, or both, may be at leastpartially integrated into a robot arm.

The cycloid gear assembly may be operatively positioned between a motor(e.g., an output shaft of a drive motor) and a driven arm of a robotassembly, or otherwise at least partially integrated with a robot arm(e.g., at least partially housed within a structure defining the robotarm). Desirably the operative relationship between a motor and a robotarm is such that output (e.g., rotary output) from a drive motor (e.g.,a servo motor) serves to rotatably drive a cycloid gear (such as about arotational axis of drive motor). The cycloid gear has a periphery (e.g.,an outer periphery) that rotates in a generally eccentric manner. Theperiphery may include teeth or some other surface that operativelyengages a fixed structure associated with a base of the robot arm. Oneor more output members (e.g., collector pins, such as made of bearingsteel), which may be in driven relationship with the cycloid gear,collect rotary motion from the cycloid gear, while essentially ignoringorbital motion of the cycloid gear. The output members, in turn, rotateabout a rotational axis of the cycloid gear. In turn, from the rotation,the output members cause a driven portion of the robot arm to move. Thecycloid gear assembly (or another gear reduction assembly) as describedabove may be employed with one or more (or all) of the motors employedherein.

Another gear reduction mechanism or gear reduction mechanism stage maybe employed instead of or in addition to the cycloid gear reductionmechanism (e.g., before the cycloid gear reduction mechanism, after thecycloid gear reduction mechanism, or generally simultaneously with thecycloid gear reduction mechanism). For example, a suitable planetarygear reduction mechanism may be employed. The elongated drive shaftattachment portion coupled with the motor output shaft (e.g., driveshaft) may be operatively in engagement with an eccentric drive portion.The eccentric drive portion may include a planetary gear assembly. Forexample, the planetary gear assembly may include a planet carrier thatmounts to an eccentric structure and operatively receives elements ofthe planetary gear assembly that may include a centrally disposed sungear, a plurality of radially disposed planet gears, and acircumscribing ring gear. The planet gears may be adapted for rotationby way of a plurality of respective axles that are received within thegears and the planet carrier. The gear ratio may be about 3:1, 4:1, 5:1,6:1 or higher. The eccentric structure may include an elongated shaftportion having a plurality of eccentrics that are out of phase with eachother and formed or attached to the shaft. The eccentric structure mayfunction as an axle in the gear reduction mechanism. The planetary gearassembly may be adapted to be carried within an output structure of thegear reduction assembly (e.g., a torque plate), carried within andbetween the driven arm and the eccentric structure serving as an armpivot axle, or both. The torque plate may contain the gears axially,which may function to be driven by one arm and to drive another arm. Atorque tube may be welded or otherwise attached to the torque plate.Both arms driven by the first motor may be connected to the torque tube.

The apparatus of the present teachings may be employed in combinationwith one or more work stations along which a work-piece is advanced. Theapparatus of the present teachings may be employed in combination withone or more work-piece support members (e.g., one or more slats, walls,and/or beams). The apparatus of the present teachings may be employedwith one or more work-piece shaping stations, such as a press. The oneor more work stations may include work-piece modification tooling, oneor more work-piece support members, or both. The one or more work-piecesupport members serve to support a work-piece as the work-piece isadvanced in a downstream direction along the apparatus, and while thework-piece engagement structures are returned in an upstream directionalong the apparatus. The one or more work-piece support members may bestationary. For example, they may be fixed in position by one or moreposts or other upright structures. The upright structures may be securedor rest upon the apparatus support structure (e.g., a sub-plate or abolster plate). The one or more work-piece support members may have agenerally flat upper surface for contacting a work-piece (or pluralityof work-pieces). The one or more work-piece support members may includeone or more notches, cut-outs, grooves, slits, or other openings intowhich one or more work-pieces are supportably received. The one or morework-piece support members may be positioned between and/or outside ofthe elongated work-piece engagement structures. The one or morework-piece support members may be positioned generally parallel with thework-piece engagement structures. The one or more work-piece supportmembers may be positioned so that as any work-piece engagement structureadvances a work-piece, such work piece engagement structure elevatesabove an upper surface of the work-piece support members. Otherarrangements are also possible. For example, the one or more work-piecesupport members may carry a support surface from a lower surface of thework-piece support member. For example, there may be a hook, a well, orthe like that hangs below the work-piece support member and into whichan advancing work-piece is received, without elevating the work-piece orthe elongated support member above the height of the upper surface ofthe work-piece support member.

Either or both of any elongated support structure or work-piece supportmember may have one or a plurality of longitudinally oriented spacedopenings (e.g., throughholes and/or elongated slots). Such openings mayreceive one or more pins or fasteners. For example, one or more openingsin the elongated support structure may receive hardware for pivotallycoupling an arm (e.g., a robot arm as described herein).

The apparatus support structure may include one or a plurality of slots.For example, it may include a plurality of slots oriented transverselyand/or in a parallel direction relative to the direction of travel of awork-piece. Any such slots may extend from one side of the apparatussupport structure to the other side, or only partially therebetween. Theslots may be generally an inverted T-shaped. Hardware mounted to theapparatus support structure via the slots may have a complementaryinverted T-shape, so that the hardware resists pulling through the slotsby lateral projections. Due to the spacing and number of slots, it ispossible to vary the arrangement of components on the structure to meetthe dimensional needs for a particular application.

As will be appreciated, any of a number of combinations of motors,gearbox structures, robot arms, and/or support structures or workstationconfigurations may be employed. It is possible that a robot arm will befree of any gear reduction structure. It is possible that a robot armwill have a portion that is integrally formed with the arm to include orotherwise house a portion of the gear reduction structure. Multiple armsmay be employed. A single robot arm may be operatively connected to twomotors. A single motor may operatively drive multiple robot arms. One ormore robot arms may be carried on a common transverse shaft.

Various teachings herein may be employed in various applications. Theteachings are not limited to a walking beam apparatus. It is possiblefor the teachings to be implemented in a number of work-piece transferoperations. One approach contemplates employing a press that includes acrown, a bolster/bolster plate, or both. Robotic arms as taught in thepreceding text may be mounted to a bolster plate of the press. Roboticarms may be mounted to a crown of a press. Robotic arms may be mountedat an intermediate location between the bolster and the crown of apress, such as at one or more upright support members. The press mayhave a forward portion, a rearward portion and opposing side structuresthat extend between the forward and rearward portions. The press mayhave a longitudinal axis and a transverse axis. The robotic arms may bemounted in a direction so that they have an axis of rotation that isgenerally parallel with the longitudinal axis of the press, thetransverse axis of the press, or a direction in between.

A suitable mounting structure may be employed for securing the roboticarms to the press. The robotic arms may be secured to the press by abase. For example, the base may include a cross member that extendsbetween opposing upright support members of the press and the crossmember is mounted to the upright support members. The base may include astanchion or other support member for attaching and/or securing therobotic arms to the bolster plate of a press or the crown of a press.

The robotic arms for use in this application may include one, two,three, or more servo motors for effectuating motion of the arms. Theremay be one, two, three, or more cycloid assemblies that definerotational joints (e.g., the area where arms are joined or connected).For example, one approach may be to employ a mounting structure that isfixedly attached to upright support members of a press. Attached to themounting structure will be a first joint that includes a portion thatconnects to a mounting bracket, a robot arm that is coupled with theconnection portion and includes an integrated gear box, a motor thatdrives the gear box for effectuating rotation of a first robot arm aboutan axis that is generally parallel with the axis of the mountingstructure. Toward an opposite end of a first robot arm, there will be asecond joint that includes a second gear box and a motor foreffectuating rotation of a second robot arm in a direction that differs,or is the same, from the direction of the first robot arm. The secondrobot arm is connected to a third joint (effectively a wrist joint) thatcan, in turn, attach to a work-piece engagement structure or tool. Thethird joint may help to keep the work-piece engagement structure or tooloriented in a desired position. One or more motors may be associatedwith the third joint and work-piece engagement structure. For example, amotor acting as a wrist motor may help to keep the work-piece engagementstructure in the desired position (e.g., to maintain desired orientationeven as the arms are moving). A linear actuation motor may also beemployed to provide linear motion actuation of the work-piece engagementstructure or tool. The motor may employ linear motion directly or mayinclude methods of converting rotary motion (e.g., from a rotary motor)to linear motion. This can be accomplished using methods such as a leadscrew drive, belt drive, or linear servo motor drive. This may allow formovement of the work-piece engagement structure in a direction that isgenerally perpendicular to the axis of rotation of the first robot arm,second robot arm, or both. Effectively, rotation about three respectiveaxes can be accomplished. Labels such as first robot arm and secondrobot arm and first motor and second motor are used herein for clarityto differentiate one arm or motor from another. The first robot arm, forexample, is not limited to the arm that is coupled to a mountingbracket. Instead, the first arm can be the arm coupled to a work-pieceengagement structure, for example.

With reference to FIGS. 1 through 4 b, there is illustrated a work-piecetransfer apparatus 10 for a multi-station work-piece operation system.The apparatus is a walking beam apparatus. The apparatus includes atleast one generally elongated work-piece engagement structure 12. It isshown as having a pair of generally parallel structures 12. Thework-piece engagement structure 12 may be adapted to support or carryfinger members 12′ (which may form a part of the apparatus) or anothersupported structure, such as a work-piece. The work piece engagementstructure 12 may instead include one or more recessed portions ordepressions to serve as a nest for a work-piece. Any work-pieceengagement structure may be suitably configured for receiving and/ortransporting a desired work-piece. It may include one or a plurality offinger projections for supporting at least a portion of a work-piece,one or a plurality of nests, notches or other depressions for receivingat least a portion of a work-piece, or both. The apparatus may includeat least one first robot arm 14 having a first end portion 16 and asecond end portion 18, the first end portion 16 being pivotallyconnected to the at least one generally elongated work-piece engagementstructure 12 (e.g., via downward projections 20). As seen, the robotarms herein may have one end that is wider than an opposing end.

A first motor 22 (e.g., a servo motor, which may be programmablyoperated or controlled) may be coupled (e.g., pivotally or in a fixedrelationship) to the at least one first robot arm 14 at the second endportion 18. The coupling is such that it allows for translating the atleast one first robot arm 14 fore and aft in a generally horizontaldirection.

A second motor 24 may be employed. The second motor may be coupled withat least one second robot arm 26 having a first end portion 28 and asecond end portion 30, the first end portion of the at least one secondrobot arm being in operating driving relationship with the second motor,and the second end portion operatively coupled with the at least onegenerally elongated work-piece engagement structure (e.g., via the atleast one first robot arm) for raising and lowering the at least onegenerally elongated work-piece engagement structure. The second motor 24is seen as being generally fixed in place. The first motor 22, however,may be translatable, such as in response to motion caused by the secondmotor.

A support structure 32 (e.g., a sub-plate or bolster plate) may beemployed for supporting the first and second motor, the at least onefirst robot arm, the at least one second robot arm, and the at least onegenerally elongated work-piece engagement structure. As can beappreciated from the drawings, the first and second motors can beoperated synchronously to raise and lower the at least one generallyelongated work-piece engagement structure, and translate the at leastone generally elongated work-piece engagement structure in a fore andaft direction by way of one or both of the at least one first and secondrobot arms. The shafts may be supported by a stanchion 32′ or othersuitable fixed base having an opening therein for receiving the shaft.

As noted, the apparatus may include at least two generally parallel andspaced apart generally elongated work-piece engagement structures 12.The at least two generally parallel and spaced apart generally elongatedwork-piece engagement structures may be supported by at least one commontransverse shaft 34. The at least one common transverse shaft 34 may beadapted to be driven by at least the first motor 22. It may also bedriven indirectly by the second motor 24, inasmuch as the second motor24 may cause the first motor 22 to raise or lower along with the shaft34.

The apparatus may include a transverse shaft 36 that is adapted to bedriven by the second motor 24.

With reference again to the apparatus as a whole, it is seen that athird motor may be employed downstream to supplement either or both ofthe motions caused by the first and/or second motors. For instance, athird motor 38 may be adapted for performing a similar function as thesecond motor 24 and/or the first motor 22.

One or more robot arms may be shaped to have rounded ends. One end mayhave a radius of curvature that is larger than the radius of curvatureat the other end. Side walls may be wider apart at the end having thelarger radius of curvature and may taper toward the end with the smallerradius. The robot arms may be configured to receive at least a portion(and conceal from view) of a gear reduction mechanism, such as a cycloidgear assembly. One or more of the robot arms may have the shape of FIG.4a . The robot arms may be adapted to receive one or more transverseshafts. For example, as seen in FIG. 4a , they may include an opening 40for receiving one of the transverse shafts (e.g., in a fixedrelationship as shown in FIG. 4b , or alternatively in a pivotalrelationship (such that it may include a generally circular or otherwiserounded opening)). One or more arms may include another opening (e.g.,an opening 42 as in FIG. 4a ) for defining a pivotal connection with thework-piece support structure. As can be appreciated from the drawing ofFIG. 4a , the opening 40 adjoins a slit 40 a the width of which can beadjustably opened or closed, such as by a screw 40 b that can be used tocompressively attach the arm around a shaft.

One or more bearings (e.g., bearings 44) may be employed at thelocations where any of the robot arms are coupled with the shafts, themotors or both. It is possible that one or more robot arms may becoupled to a shaft in a pivotal manner by employing a cross-sectionedshaft of any shape that penetrates a complementary-shaped opening in abearing.

With more attention to the structure of an illustrative cycloid gearreduction mechanism of the teachings herein, reference is made to anexample depicted in FIGS. 5-9. By way of illustration, withoutlimitation, a gear reduction mechanism (e.g., a cycloid gear assembly50) may be operatively connected with an output drive structure of oneor more of the motors (e.g., motors 22, 24, 38). Referring to FIGS. 6-8,it is seen that a motor drive shaft 52 having a longitudinal axis,extends from a motor 54 (e.g. at an end 54 a of the motor 54). The motormay be a suitable servo motor (e.g. a servo motor that is programmablyor otherwise controllably operated to deliver rotary driving output tothe motor drive shaft, which can be employed for driving the cycloidgear assembly). The output drive structure (e.g., drive shaft 52) isadapted to drive an eccentric assembly 56. The eccentric assembly mayinclude one or a plurality of eccentrics, with or without an associatedeccentric bearing. For example, an assembly may be suitably balanced,such as by employment of two or more out of phase eccentrics 56′. Asseen in FIGS. 5 and 6, one or more eccentrics may be carried on a shaft58 (e.g., a hollow shaft) having a longitudinal axis. The longitudinalaxis of the shaft 58 may be generally in alignment with the axis ofrotation of the motor shaft 52. The shaft 58 may be coupled with themotor drive shaft 52 (e.g., it may be integrally formed with the driveshaft, or otherwise matingly fitted over or within the drive shaft). Asnoted, the eccentric assembly may include multiple (e.g. two or more)eccentrics 56′. The multiple eccentrics may be longitudinally disposedrelative to the longitudinal axis of the drive shaft. They may be out ofphase relative to each other (e.g. two eccentrics that are 180° out ofphase with each other). The multiple eccentrics may be adjoining. Theymay be spread apart from each other (e.g. they may be longitudinallyspaced so that opposing faces may have a gap between them, for examplethe gap may range from about 0.5 mm to about 50 mm, or about 2 mm toabout 30 mm).

One or more cycloid gears 60 may be driven by the one or more eccentrics56′. For example, two or more cycloid gears 60 may be employed that aredriven by two or more respective eccentrics that are out of phase suchas for achieving a balanced operation. The cycloid gears may have agenerally central opening 62. The opening, which may be a throughholeopening may receive an eccentric (or a bearing associated therewith).

The one or more cycloid gears (which may be generally round and have aplurality of spaced apart teeth about its periphery) may include one ormore throughhole openings, such as a plurality of radially disposedthroughhole openings. The throughhole openings may be generally roundand have a diameter or other inner peripheral dimension. For example, asseen in FIG. 9, a plurality of radially spaced throughhole openings 64are formed in the cycloid gear 60. The throughhole openings aregenerally circular and have a diameter. A periphery 66 of the cycloidgear 60 is generally round, and has a plurality of teeth 68 spaced apartfrom each other. Two or more of the cycloid gears may be such that theirrespective throughhole openings 64 and/or generally central opening 62are generally in registered alignment with each other.

The cycloid gear may be part of an assembly that includes at least oneinner race 70. The inner race 70 may be configured to co-act with theperiphery of the cycloid gear, such as by way of an inner peripheralsurface of the inner race. The Inner race may function as the axle inthe gear reduction mechanism. The inner race may have a plurality ofpockets (e.g., on an inner peripheral surface) that receive rollingelements 72 (e.g., in an amount larger than the number of teeth of thecycloid gear). The inner race generally circumscribes the cycloid gearperiphery, and may be spaced at least partially about the periphery ofthe cycloid gear. For example, the inner race 70 generally surrounds thecycloid gear and may be spaced apart from the cycloid gear 60, exceptfor locations where gear teeth of the cycloid gear and the rollingelements intermeshingly engage.

As seen in one illustrated embodiment, the inner race may have agenerally circular outer peripheral wall. The inner race may have agenerally circular inner wall which may have a plurality of pockets toreceive the rolling elements 72. The inner wall of the inner race may bein generally opposing relationship with the periphery of the cycloidgear. The inner wall of the inner race may be adapted so that as thecycloid gear is rotated (e.g. by the rotation of the motor drive shaft52) a portion of the outer periphery of the cycloid gear radiallyadvances toward a portion of the inner wall of the inner race (see FIG.9). Simultaneously a portion of the outer periphery of the cycloid gearretreats away from the inner wall of the inner race.

The inner race and the cycloid gear may have a space between them havinga plurality of rolling elements (e.g., elongated cylindrical pins,balls, or other rolling elements). For instance the inner surface of theinner race may include a plurality of circumferentially disposed spacesbetween gear teeth (e.g., pockets) for receiving the rolling elementsand thereby defining a rolling element carriage structure.

The outer wall of the inner race may have a cross sectional profile. Theprofile may be such that the outer wall of the inner race is adapted torotatably co-act with an inner wall of an outer race, such as byreceiving one or a plurality of rolling elements. For example, it mayhave a generally flat bottom, an arcuate bottom, or both (e.g. a bottomthat has a hemispherical indentation). The profile may have opposingupright walls (which may be generally perpendicular to the bottom). Itmay have a top wall that may be generally flat or include one or moreflat portions. It may include an indentation. It may have a suitableconfiguration to receive one or more rolling elements in a space betweenthe inner race and an outer race 74 (e.g., in a space between the outerwall of the inner race and an inner wall of the outer race. The profilemay be generally constant around the inner race. As seen, for example,in FIGS. 5 and 6, the cross sectional profile has a generally flatbottom wall, two generally upright (e.g. perpendicular to the bottomwall) side walls, and a top wall that has a generally flat portion and acentrally disposed indentation.

An average diameter of the cycloid gear relative to the average innerdiameter of the inner race may be smaller. The average diameters may bethe diameters that take the average depth from crests to bottoms of thegear teeth. The relative size of the diameters may be such that as theeccentric shaft rotates through a single revolution, the cycloid gearrotates in a counter direction by less than a single rotation (e.g. theratio of rotation of the inner race relative to a rotation of thecycloid gear range from about 5:1 to about 95:1). The inner race maylocated at least partially within an outer race, e.g., they may eachhave a common or generally parallel plane of rotation (e.g., a planethat intersects at right angles with an axis of rotation).

The inner race 70 and the outer race 74 of the assembly herein may bepositioned for rotational motion relative to each other. The outer racemay have an Inner circumferential wall that generally surrounds theouter periphery of the inner race. For example, one of the inner race orouter race may be maintained in a fixed operational position relative tothe other race. For maintaining in a fixed position, one of the racesmay be secured to a fixed structure of a robot arm, such as a mountingfoot 76 for a robot arm (such as the stanchion 32′ of FIGS. 1 and 2).For instance, one or more fasteners 78 (e.g., head cap screws) maysecure the inner race to the mounting foot 76, or to a drive member of arobot arm. The outer race 74 may be held in a fixed position to a drivenportion 80 of the robot arm. For instance, it may be mounted by one ormore fasteners (e.g. head cap screws 82) to the driven portion 80.Either or both of the outer race or inner race may be made of oneintegrated piece or a plurality of discrete pieces.

Within each of a plurality of (if not all of) the radially disposedthroughhole openings of the cycloid gear may be a suitable memberadapted for converting the rotational motion of the cycloid gear intorotary motion for driving a driven portion of a robot arm. For example,a plurality of collector pins 84 may have a diameter that is smallerthan the diameter of the throughhole openings. In this manner therotation of the cycloid gear is collected by the pins, which may alsoeffective ignore orbital motion of the cycloid gear. The collector pins(which may have a longitudinal axis that is generally parallel to thelongitudinal axis of the motor drive shaft) may be held in place by oneor more bearings (e.g., bearings 86). Such collector pin bearings may beadapted to allow the pins to rotate freely about their rotational axes.Such collector pin bearings may be disposed within a driven portion of arobot arm. For example, bearings 86 may each disposed within a pocket ofa driven portion 80 of a robot arm. One or more additional bearings 88may be employed for aiding rotation of the driven portion of the robotarm.

As can be appreciated from the above, and taking into account theexample illustrated in FIGS. 5-9, when the motor 54 rotates its driveshaft 52 about a drive shaft rotational axis, the drive shaft causes thecycloid gear 60 to rotate about a rotational axis (by way of theeccentrics), which, for example, may be aligned with or parallel to thedrive shaft rotational axis. The cycloid gear 60 causes the collectorpins 84 to rotate (both about their own respective rotational axes andabout the rotational axis of the motor drive shaft and the cycloidgear), in turn, translating the driven portion 80 of the robot arm. Gearreduction is thus possible. As also seen, in accordance with the generalteachings herein applicable to other embodiments, components of the gearreduction mechanism may be integrated as part of a robot arm. Forexample, operative components of the gear reduction mechanism may bemachined or otherwise formed as part of the robot arm (e.g., an endportion of a robot arm (such as a driving end portion that also carriesa motor) may be machined or otherwise formed to receive a plurality ofcollector pins for facilitating a cycloid gear rotation).

As can be gleaned from the teachings and illustrative examples herein,components can be interchanged so that associated with a driving portionof the robot arm (e.g., the portion of the arm connected to the foot)may be the outer race, and the driven portion of the robot arm mayinclude the inner race.

FIGS. 10A and 10B illustrate exploded views of an assembly employing amotorized drive portion coupled with a mount portion for fixing theposition of the drive portion. A gear reduction portion housed at leastpartially within the robot arm causes controlled output from themotorized drive portion to drive a robot arm (e.g., by output from themotorized drive portion and a planetary gear reduction mechanism and/ora cycloid gear reduction). The cycloid gear reduction generallyfunctions consistent with the embodiment of FIGS. 5-9. Features shown inthe embodiment of FIGS. 5-9 may be employed in this embodiment, and viceversa. As shown, a second motor 24 is generally fixed in place (e.g., toa stanchion or base 32′). A first motor 22 may be translatable (e.g.,relative to the second motor 24), such as in response to motion causedby the second motor 24. The apparatus may include a plurality (e.g., apair) of common transverse shafts 34 and 36. The at least one commontransverse shaft 34 may be adapted to be driven by at least the firstmotor 22. It may also be driven indirectly by the second motor 24,inasmuch as the second motor 24 may cause the first motor 22 to raise orlower along with the shaft 34. The apparatus may also include atransverse shaft 36 that is adapted to be driven by the second motor 24.

The motors each include a motor adapter (e.g., a plate) 162 for securingthe motors within the assembly. For example, a motor may be attached toa motor adapter (such as by fasteners and/or integrally formed). Theadapter in turn may be secured within a stanchion 32′, a robot arm(e.g., a recess formed in an end of the robot arm), or otherwise. Thefirst motor 22 is coupled with a first robot arm 14 that is adapted fortranslating the first robot arm 14 in a fore and aft, generallyhorizontal direction. The first robot arm 14 may be any shape, dependingupon the application. The first robot arm 14 may be shaped similarly tothe first robot arm depicted in FIG. 4a , which receives a shaft andtranslates the work-piece in a generally horizontal direction, such asfor achieving a pitch during work-piece operations. One or more of themotors (e.g., the second motor 24 of FIGS. 10A and 10B) may be supportedby a stanchion 32′ or other base or support member. In this illustrativeexample, the second motor 24 includes an elongated drive shaftattachment portion 190 located on the drive shaft of the motor 24 thatengages with the gear reduction mechanism (e.g., operatively engagedwith the eccentric assembly 56 and/or a planetary gear assembly). Withinthe assembly is an end cap 164 with an opening that encircles theelongated drive shaft attachment portion 190. A spacer 168 is locatedwithin a bearing 166 and provides a space between the end cap 164 andthe eccentric assembly 56. The eccentric assembly 56 may serve as anaxle for the gear reduction mechanism and may include one or more out ofphase eccentrics 56′. A bearing retainer 170 is generally located at theopposing end of the eccentric assembly. One or more cycloid gears 60 mayalso be located within the assembly and may include one or more openingsor areas for receiving one or more collector pins 84.

The assembly includes a second robot arm 26 that functions to allow forraising and lowering of the at least one work-piece. A planetary gearreduction may assist in the raising and lowering using the second robotarm 26, the first robot arm 14, or both. The planetary gear reductionassembly may include a spacer 168 to provide space between a portion ofthe second robot arm 26 and other elements of the assembly. Theplanetary gear reduction assembly includes a bearing 166. The planetarygear assembly includes a planet carrier 172 that mounts to the eccentricassembly 56 and operatively receives elements of the planetary gearassembly. The planetary gear assembly includes a plurality of planetgears 174 that engage with and rotate around a centrally located sungear 176. The plurality of planet gears and/or the sun gear include anaxle 182 and a bearing 184 disposed therein. The planet gears areadapted for rotation by way of the respective axles 182 received withinthe gears and the planet carrier 172. The gears are circumscribed by aring gear 178. The opposing face of the planetary gear assembly isadapted to be carried on a torque plate 180.

The elongated drive shaft attachment portion 190 that engages with thegear reduction mechanism (e.g., cycloid gear reduction, planetary gearreduction, or both) is shown in greater detail in FIG. 11A. Theelongated drive shaft attachment portion 190 includes a first motorconnection portion 192 which is located over the drive shaft of a motor,such as the second motor 24 of FIGS. 10A and 10B. The elongated driveshaft attachment portion 190 joins the first motor connection portion192 and a gear box interface portion 194, which includes an engagementportion 196 that interfaces with the gear reduction mechanism (e.g., bya male/female connection). The engagement portion 196 may have one ormore flat side surfaces. They are generally rectangular in cross-sectionprofile in this illustrative example. The first motor connection portion192 is generally hollow along a portion of its length. It may be oblongon an inside wall in its transverse cross-section, as is shown in FIG.11B, which is the cross section of the elongated drive shaft attachmentportion 190 of FIG. 11A taken at line B,C. When pressure is applied, thefirst motor connection portion 192 can be placed over the motor driveshaft, which may be generally cylindrical, as is shown in FIG. 11C,which is the cross section of the elongated drive shaft attachmentportion 190 of FIG. 11A taken at line B,C, when pressure is applied.When the pressure is released, the elasticity of the material may causethe inner wall to generally return to its original shape, as shown inFIG. 11B, which engages with the motor drive shaft (e.g., in a press-fitand/or frictional manner).

As can be appreciated from the above, and taking into account theexample illustrated in FIGS. 10A and 10B, when the motor 24 rotates itsdrive shaft about a drive shaft rotational axis, the drive shaft causesthe sun gear 176 and/or the planet gears 174 to rotate about a rotationaxis, which, for example, may be aligned with or parallel to the driveshaft rotational axis and causes the cycloid gears 60 to rotate about arotational axis (by way of the eccentrics). Gear reduction is thuspossible. As also seen, components of the gear reduction mechanism maybe integrated as part of a robot arm.

It is contemplated that the first motor 22 acts through its own gearreduction mechanism to drive the first arm 14 or directly drive thework-piece engagement structure (see FIG. 1). Any motor of the assemblyof any of the figures herein may be controlled to raise or lower an arm.Any motor may be controlled to achieve fore and aft motion (e.g., in agenerally horizontal direction) of an arm. This movement can beperformed by the same motor or different motors. This movement can becontrolled by a controller (not shown) to achieve a desired translationpath.

Other variations of the teachings herein are also possible. Asillustrated, but without limitation, a pair of transverse shafts may belocated at the upstream and downstream portions (e.g., end portions) ofthe apparatus. There may be a pair of transverse shafts, each located atopposing upstream and downstream portions of the apparatus. The shaftsmay have a cross-sectional shape that differs along the length of theshaft. For example, one or more of the shafts may be generallyrectangular in a region for fixedly engaging a robot arm at one endportion. One or more of the shafts may be generally circular forpivotally engaging the same robot arm at another end portion. The shaftsmay be such that the shape extends at least a portion of the length sothat the robot arms may be slidably adjustable along that portion of thelength. The shafts may be configured for allowing translation of one ormore arms (e.g., robot arms) at least partially along their length.

It will be appreciated from the present teachings that the apparatus mayemploy only a single motor (e.g., the first motor 22) for performing thefunction of translation in the fore and aft direction. A plurality ofmotors may be employed as well (e.g., two, three, four or more motors).A single motor or a plurality of motors may be employed being adaptedfor performing the function of translation (e.g., by way of a robot armor other structure adapted for translation) of a work piece engagementstructure in the fore and/or aft direction. A single motor or aplurality of motors may be employed which may be adapted for performingthe function of raising or lowering (e.g., by way of a robot arm orother structure adapted for translation) a work piece engagementstructure. A single motor or a plurality of motors can be employed, eachbeing adapted for performing the function of raising or lowering, andcausing motion in a fore and/or aft direction (e.g., by way of a robotarm or other structure adapted for translation) a work piece engagementstructure); that is a single motor may be adapted for bothlifting/lowering and pitch translation motions. One or more (or all) ofthe motors may be located on the same side of the apparatus. Thetransverse shafts and/or the robot arms, or other structure adapted fortranslation of a work piece engagement structure, may be driven by themotors from a single side of the apparatus, or from both sides of theapparatus.

Control over robot arm translation is versatile in accordance withpresent teachings. For example, one or more of the motors herein can becontrolled (e.g., programmably controlled) for causing lifting of arobot arm from a starting position, forward translation of the arm, andthen a return of the robot arm to the starting position, therebycompleting a cycle. Lifting may include a portion of which is performedto include a generally arcuate motion, a linear motion, or both. Thearcuate motion may include a plurality of minute horizontal and verticalmovement the magnitude of which are such as to give the appearance ofarcuate motion (e.g., a radial motion). The arcuate motion may include asingle or a plurality of radial movements. The steps of performing theabove motions is part of the teachings herein as well. Cycle rates mayrange from about 5 cycles per minute to about 120 cycles per minute(e.g., about 10 cycles per minute to about 90 cycles per minute, or evenabout 15 cycles per minute to about 60 cycles per minute). A cycle mayinclude an advancing portion in which the one or more robot arms causeadvancing of a work-piece from a first location to a second locationfrom a robot arm initial position, and a returning portion in which theone or more robot arm returns to its initial position. The amount oftime that it takes for the advancing portion of the cycle may be thesame as, longer than or shorter than the amount of time for thereturning portion. For example, the ratio of the amount to time for theadvancing portion to the amount of time for the returning portion mayrange from about 6:1 to about 1:6, about 4:1 to about 1:4, or even about2:1 to about 1:2.

Control over robot arm translation may also afford introducing one ormore dwell times, during which a work-piece is maintained at a certainlocation within the system for a relatively prolonged time, such as forallowing desired operation to be performed on the work-piece, forperforming an operation upon equipment used in one of the work-pieceoperations.

The instrument can be controlled for achieving translation amounts asdesired for a particular work-piece. For example, translation amountsmay range from about 1 mm to 1000 mm (or higher) (e.g., about 5 to about500 mm, or about 15 mm to about 250 mm, or even about 25 to about 100mm).

The controlling operations may be performed by one or more controllers(e.g., programmable logic controllers) associated with one or more ofthe respective motors. Therefore, a program can string together commands(e.g., using G-code) to get the desired motion for the desiredapplication.

In operation, the at least one first motor will translate fore and aft,and the at least one second motor will translate upwardly and downwardlyin order to cause the work piece engagement structures to contact thework piece and translate the work-piece from a first upstream positionto a second downstream position. For example, the second motor may raiseand lower to come into and out of engagement with a work-piece. While ina raised and engaged position, the second motor will cause a forwardmovement of the work-piece engagement structure. After the work-piecehas been advanced downstream, the first motor will lower the work-pieceengagement structure and the second motor will translate the work-pieceengagement structure upstream where it can engage another subsequentwork-piece. The steps can be repeated consecutively.

As depicted in the drawings, translating in the fore position may entailcontrolling the apparatus for advancing a work-piece longitudinallyalong the apparatus from right to left. However, the apparatus may becontrolled for advancing a work-piece longitudinally along the apparatusfrom left to right. The apparatus may include one or more sensorsadapted for ascertaining the position of one or more work-pieces. Theapparatus may include one or more sensors for ascertaining the presenceor absence of one or more work-pieces intended to be carried by thework-piece engagement structures. Any sensors employed may be insignaling communication with a suitable controller that controlsoperation of the apparatus. For example, if a certain condition isdetected by a sensor, it may issue a signal (e.g., to the controller),which causes the controller to alter operation of the apparatus in apredetermined manner.

Other variations or features are possible in accordance with theteachings. The motors may be located below or above the work-pieceengagement structures. The motors may be located adjoining a base orsupport of the apparatus. One or more of the motors may be mounted to awork-piece shaping system, such as a press (e.g., to a crown and/or abolster of a press). Multiple motors may be employed with each having anoutput shaft having an axis of rotation. Where there are multiplemotors, the respective axes of two or more of the axes may be generallyparallel. They may be spaced apart. One of the axes may be positionedhigher than the other one. The robot arm can have one, two, three ormore pivotal joints. There may be one or more motors at each jointand/or for causing motion of at least a portion of the robot arm at suchjoints. It is also possible that the elongated work-piece engagementstructure will be transversely oriented, and/or that there will be atleast one transversely oriented elongated work-piece engagementstructure and at least on longitudinally oriented elongated work-pieceengagement structure.

The teachings herein also contemplate the subassemblies that aredescribed. For example, it is within the scope of teachings herein thatthere will be a robot arm (as taught) and/or a motor in combination withone or more gear reduction mechanisms (as taught, e.g., a cycloid gearreduction mechanism, a planetary gear reduction mechanism as described).It is contemplated that an eccentric assembly, planet gear assembly, orboth, may be employed for driving the first robot arm, the second robotarm, or both (e.g., an eccentric assembly may be located in either orboth of the openings of the second robot arm and/or associated witheither or both of the first and second motor). Mounting hardware may beused (e.g., a mounting foot or other like component for securing a robotarm, motor, and/or gear reduction mechanism to a support structure(e.g., an existing support structure, such as a crown and/or bolster ofa press)). Kits comprising any of these components and/or subassembliesare also within the teachings herein.

Turning to FIGS. 12a through 12e , there is seen an example of how anapparatus 110 of the teachings herein is employed sequentially toadvance a work-piece 100 longitudinally along the length of theapparatus, in this instance from the right side toward the left side.The apparatus 110 employs the general teachings herein (e.g., thosedescribed above and in connection with the embodiments of FIGS. 1-11 c),essentially adapted to transfer a work-piece in a direction generallyalong at least a portion of the length of the apparatus 110. Elongated(and generally parallel) work-piece structures 112 (shown as generallyrectangular slats) have a plurality of throughholes formed in them toreceive pins or other hardware for pivotally connecting arms 114 to thestructures 112. The elongated work-piece support structures 112 arepositioned between a pair of generally parallel work-piece supportmembers 150. The support members 150 are positioned above the supportstructure 132 by uprights 152. The support structure 132 is shown (byway of example only and without limitation) to include a plurality ofoptional inverted T-shaped slots 154 into which various hardwarecomponents are or can be positioned. The support members as shown inthese figures may simulate or be part of a work station for producing afinished work-piece.

In FIG. 12a , the work-piece is in a first position as it rests on thesupport members 150. In FIG. 12b , the motors cause the robot arms (viaa gear reduction mechanism (e.g., a cycloid gearing assembly such asdescribed herein) to cause the work-piece engagement structures 112 totranslate upstream at a height so that the top surface of the work-pieceengagement structures 112 is below the top surface of the work-piecesupport members 150. It is then caused to raise (FIG. 12c ) by one orboth of the motors 122 and 124 and the robot arms that they respectivelydrive, so that the work-piece is above the top surface of the supportmembers 150. Another downstream motor 138 may facilitate similardownstream motion of the elongated work-piece engagement structures 112,by way one or more of its own associated arms 114 and any associatedgear reduction mechanism. As part of that step, or by its own step, oneor more of the motors may cause the work-piece engagement structures 112to pitch forward, and thus advance the work-piece 100 at least partiallydownstream along the length of the apparatus (see FIG. 12d ). Forexample, the motor 122 may be adapted to cause the fore and aft robotarm motion for effectuating the pitch. The motors 124 and/or 138 may beemployed for raising and/or lowering the work-piece engagementstructures 112.

Turning to FIG. 13, there is seen an example of an apparatus 110employing generally the teachings herein (e.g., those described aboveand in connection with the embodiments of FIGS. 1-12 e), essentiallyadapted to transfer a work-piece in a direction generally along at leasta portion of the length of the apparatus 110. Elongated (and generallyparallel) work-piece structures 112 (shown as generally rectangularslats) have a plurality of throughholes formed in them to receive pinsor other hardware for pivotally connecting arms 114 to the structures112. The work-piece structures 112 may also include one or more fingersor other attachments for assisting in holding and/or transferring awork-piece. The support structure 132 is shown (by way of example onlyand without limitation) to include a plurality of optional invertedT-shaped slots 154 into which various hardware components are or can bepositioned. One or both of the motors 122 and 124 may cause a firstrobot arm 114 to move upward, downward, in a fore direction, in an aftdirection, or any combination thereof. One or both of the motors 122 and124 may also cause a second robot arm 126 to move upward, downward, in afore direction, in an aft direction, or any combination thereof. Adownstream motor 138 may also cause a robot arm to move upward,downward, in a fore direction, in an aft direction, or any combinationthereof. In this example, the second motor 124 is fixed to the supportstructure 132 by a stanchion 32′. The motors, stanchion, and the armsare assembled so that one or more gear reduction mechanisms are at leastpartially housed within the second robot arm 126, first robot arm 114,or both. One or more power cords 156 or other cords may connect themotors to a control panel, power source, controller, or the like.

In this regard, as part of the general teachings herein, applicable tothe various embodiments contemplated, it may be possible for one motorto be mounted to and carried on a structure translatable by anothermotor (e.g., a motor such as motor 122 may be mounted to a robot armthat is translated by another motor, such as motor 124). Thus, raisingand lowering may be performed by one motor, and pitch may be performedby another motor.

FIGS. 14 and 15 illustrate the apparatus as discussed herein installedon a press 200. The press includes a longitudinal axis LA and atransverse axis TA. The press 200 may include a crown portion 202, whichis an upper portion of the press 200 containing the drive mechanisms orcylinders that guide the reciprocating motion of a ram 204 (i.e., themain upper portion of the press that slides up and down within thepress). The press 200 includes opposing upright support members 206 thatextend upward from a bed portion 208, which is the foundation andsupporting structure of the press. FIG. 14 shows the apparatus mountedto a bolster plate 232 of the press 200 via a mounting structure such asa stanchion 232′. FIG. 15 illustrates the apparatus mounted to the press200 by a cross member 210 extending between the opposing upright supportmembers 206. The apparatus includes two opposing work-piece engagementstructures 212 for engaging and moving a work-piece through the press. Awork-piece can enter the press along the longitudinal axis LA of thepress, the transverse axis TA of the press, or at an angle in between.The orientation of the apparatus will guide the work-piece in thedesired direction.

The work-piece engagement structure 212 is coupled to a first robot arm216. A first motor 226 is located generally at the joint between thework-piece engagement structure 212 and the first arm 216. The firstmotor 226 acts as a wrist motor and allows the work-piece engagementstructure 212 (and/or the work-piece, not shown) to maintain a desiredorientation, even if other elements of the apparatus are moving. Thefirst motor 226 may allow the work-piece engagement structure 212 toraise and lower. Linear motion or translation of the work-pieceengagement structure 212 is accomplished by a linear actuation motor240. The linear translation may be in a direction generallyperpendicular to the first robot arm 216 (see FIG. 15), generallyparallel to the axis of rotation of one of the joints of the apparatus,or both, so that the work-piece can be advanced in that direction. Thislinear actuation can be accomplished by a motor actuating linear motiondirectly or by a mechanism that converts rotary motion (e.g., from arotary motor) to linear motion. Examples for actuating linear motioninclude linear servo motor drive, lead screw drive, or belt drive. Asecond robot arm 214 is coupled to the opposing side of the first robotarm 216. A second motor 224 is located generally at the joint betweenthe first robot arm 216 and the second robot arm 214. The second motor224 may enable the first robot arm 216 to raise and lower. The secondrobot arm 214 is coupled to the base (i.e., the stanchion 232′ of FIG.14 or the cross member 210 of FIG. 15). A third motor 222 is locatedgenerally at the joint between the base and the second robot arm 214.The third motor 222 may enable the second robot arm 214 to translate ina fore and aft direction, raise and lower, or both. Each apparatusincludes a parallel opposing robot arm joined to the first robot arm 216and second robot arm 214 carrying the motors. FIG. 14 also shows twoopposing apparatuses located on opposing ends of the press 200. Theparallel opposing robot arms (e.g., a first robot arm 216 and opposingfirst robot arm; second robot arm 214 and opposing second robot arm) arejoined by connecting shafts 234, 236, and 238. These connecting shaftsprovide support to the apparatus and work-piece and additional strengthfor transferring and moving a work-piece.

After the work-piece has been advanced, another cycle is started. Theelongated engagement structures are caused to lower away from thework-piece and move upstream where it will start the series of motionsover again.

The system herein may be operated by one or more switches and/orsignaling sources or circuits for supplying the motors with a source ofpower.

Units depicted in the drawings are illustrative and not intended aslimiting. They may vary as necessary for achieving the appropriatetranslation. Relative proportions depicted in the drawings are part ofthe teachings even if not expressly recited herein.

The disclosures of all articles and references, including patentapplications and publications, are incorporated by reference for allpurposes. The term “consisting essentially of” to describe a combinationshall include the elements, ingredients, components or steps identified,and such other elements ingredients, components or steps that do notmaterially affect the basic and novel characteristics of thecombination. The use of the terms “comprising” or “including” todescribe combinations of elements, ingredients, components or stepsherein also contemplates embodiments that consist essentially of, oreven consisting of, the elements, ingredients, components or steps.

Plural elements, ingredients, components or steps can be provided by asingle integrated element, ingredient, component or step. Alternatively,a single integrated element, ingredient, component or step might bedivided into separate plural elements, ingredients, components or steps.The disclosure of “a” or “one” to describe an element, ingredient,component or step is not intended to foreclose additional elements,ingredients, components or steps.

Relative positional relationships of elements depicted in the drawingsare part of the teachings herein, even if not verbally described.Further, geometries shown in the drawings (though not intended to belimiting) are also within the scope of the teachings, even if notverbally described.

What is claimed is:
 1. A work-piece transfer apparatus comprising: a. atleast one generally elongated work-piece engagement structure; b. atleast one first robot arm having a first end portion and a second endportion, the first end portion being pivotally connected to the at leastone generally elongated work-piece engagement structure; c. a firstmotor coupled to the at least one first robot arm at the second endportion and being adapted for translating the at least one first robotarm fore and aft in a generally horizontal direction; d. a second motor;e. at least one second robot arm having a first end portion and a secondend portion, the first end portion of the at least one second robot armbeing in operating driving relationship with the second motor, and thesecond end portion operatively coupled with the at least one generallyelongated work-piece engagement structure for raising and lowering theat least one generally elongated work-piece engagement structure; and f.a support structure for supporting, from below, the first and secondmotor, the at least one first robot arm, the at least one second robotarm, and the at least one generally elongated work-piece engagementstructure; wherein the first and second motors are operatedsynchronously to raise and lower the at least one generally elongatedwork-piece engagement structure, and translate the at least onegenerally elongated work-piece engagement structure in a fore and aftdirection by way of one or both of the at least one first and secondrobot arms.
 2. The apparatus of claim 1, wherein the apparatus includesat least two generally parallel and spaced apart generally elongatedwork-piece engagement structures.
 3. The apparatus of claim 1, whereinthe apparatus includes at least two generally parallel and spaced apartgenerally elongated work-piece engagement structures that are supportedby at least one common transverse shaft.
 4. The apparatus of claim 1,wherein the apparatus includes at least two generally parallel andspaced apart generally elongated work-piece engagement structures thatare supported by at least one common transverse shaft that is adapted tobe driven by the second motor.
 5. The apparatus of claim 1, wherein theapparatus includes a transverse shaft that is adapted to be driven bythe first motor.
 6. The apparatus of claim 1, wherein the apparatusincludes one or more generally elongated work-piece engagementstructures that each are adapted for pivot connection to the at leastone first robot arm by way of a downward projection located toward anend of the one or more generally elongated work-piece engagementstructures.
 7. The apparatus of claim 1, wherein the one or moregenerally elongated work-piece engagement structures carry a pluralityof transversely extending fingers.
 8. The apparatus of claim 1, whereinone or both of the first and second motors are servo motors.
 9. Theapparatus of claim 1, wherein the apparatus includes at least twogenerally parallel and spaced apart generally elongated work-pieceengagement structures that are supported by a pair of spaced aparttransverse shafts, wherein one transverse shaft is driven by at leastthe first motor and another transverse shaft is adapted to be driven bythe second motor.
 10. The apparatus of claim 1, wherein the apparatusincludes at least two generally parallel and spaced apart generallyelongated work-piece engagement structures that are not joined together.11. The apparatus of claim 1, wherein a cycloid gear assembly is housedwithin one or more of the robot arms.
 12. The apparatus of claim 1,wherein one of the first or second motor is mounted in a fixed position,and the other of the first or second motor is mounted for translation toa structure that is driven by the motor mounted in a fixed position. 13.The apparatus of claim 1, wherein the apparatus includes a motor forenabling linear motion of the at least one generally elongatedwork-piece engagement structure in a direction parallel to alongitudinal axis of the at least one generally elongated work-pieceengagement structure.
 14. A work-piece transfer apparatus comprising: a.at least one generally elongated work-piece engagement structure; b. alinear actuation motor coupled with the at least one generally elongatedwork-piece engagement structure; c. at least one first robot arm havinga first end portion and a second end portion, the first end portionbeing connected to the at least one generally elongated work-pieceengagement structure, d. a first motor coupled to the at least one firstrobot arm and at least one generally elongated work-piece engagementstructure; e. at least one second robot arm coupled with the second endportion of the at least one first robot arm; f. a second motor coupledto the at least one first robot arm and the at least one second robotarm; g. a base for supporting the at least one first robot arm, the atleast one second robot arm, and the at least one generally elongatedwork-piece engagement structure and mounting the apparatus to astructure; and h. a third motor coupled to the base and the at least onesecond robot arm; wherein the linear actuation motor is operated toprovide linear movement in a longitudinal or transverse direction inrelation to the structure; wherein the first motor is operated tomaintain a desired orientation of the least one generally elongatedwork-piece engagement structure; and wherein the second and third motorsare operated synchronously to raise and lower the at least one generallyelongated work-piece engagement structure, and translate the at leastone generally elongated work-piece engagement structure in a fore andaft direction by way of one or both of the at least one first and secondrobot arms.
 15. The apparatus of claim 14, wherein the base is astanchion for mounting the apparatus to the structure.
 16. The apparatusof claim 14, wherein the base is a cross member for mounting theapparatus to an upright support member of the structure.
 17. Theapparatus of claim 15, wherein the structure is a press.
 18. Theapparatus of claim 17, wherein the press includes two or more of theapparatus arranged on opposite sides of the press.
 19. The apparatus ofclaim 14, wherein a cycloid gear assembly is housed within one or moreof the robot arms.
 20. The apparatus of claim 14, wherein one or more ofthe first motor, second motor and third motor is a servo motor.